Earthquake swarm in Presthnjúkar volcano. Update on Katla volcano

Presthnjúkar volcano: Few days ago an earthquake swarm did start in Presthnjúkar volcano. This earthquake swarm is entirely tectonic in nature. There is nothing that suggests that this earthquake swarm is connected to magma movements inside Presthnjúkar volcano system. So far this earthquake swarm has been slow and small. But the largest earthquakes have gone up to ML3.3 in size according to Icelandic Met Office.


The location of current earthquake swarm in Presthnjúkar volcano. Copyright of this picture belongs to Icelandic Met Office.

Katla volcano: Over the last 18 hours it has been quiet in Katla volcano. As no more earthquakes have been detected from it. I would not be surprised if there are more earthquakes swarms in Katla volcano in the next few weeks and months. It is an well known fact that Katla volcano is heading to an eruption. But nobody knows when that is going to happen.


Location of the earthquakes in Katla volcano yesterday. Copyright of this picture belongs to Icelandic Met Office.

Besides this two highlights of earthquake activity in Iceland. It has been rather quiet in the past few weeks. With just from ~100 to ~300 earthquakes during the week.

134 Replies to “Earthquake swarm in Presthnjúkar volcano. Update on Katla volcano”

  1. Hmm something is up with the SIL stations around Myrdalsjökull. Tremors are increasing. Best visible on GOD SIL station.

    Weather seems calm enough not to have such an impact on the tremorcharts.

    1. However this seems only to affect the high frequency 2-4 Hz band. The others are seemingly unaffected.

      1. Well not “proves” as such but it makes it highly likely. And I bet the geologists has already read the charts and come to the conclusion that they are indeed tectonic.

        Rather large coincidence though since they appeared on the same spot as the volcano is. But maybe that area is more prone to fracturing than the surrounding area.

    1. No… it doesn’t “prove” it, it just places more evidence in that direction.

      Analysis of the focal mechanism would “prove” that, but I don’t have access to that sort of data.

      Now… for the more useful (to some) view angles… same data.

      View North

      http://i55.tinypic.com/iy0i94.png

      View East

      http://i54.tinypic.com/9g98id.png

      And the perverted view… up the skirt. Actually an along axis view of the faulting trend of the area. Not quite 45°, but along the axis.

      http://i52.tinypic.com/rrij6a.png

      1. Well, they are spread quite well. I would not be surprised if they still were magmatic. I think they may be tectonic, but there is always a possibility for magma rising along the known fault. Hence I’d be interested to see the time vs. depth plot, which could act as a “referee” for this question.

  2. At first I thought that it was weatherinduced since only the 2-4 Hz band was affected but I now see that the others are also affected albeit in a smaller scale.

    Jón correct me if I am wrong here but doenst it look very much like a harmonic tremor spike?

    I might be way off on this one and probably I am..;) So no repost of this on GLP please..;P

  3. There was an harmonic tremor spike in Katla volcano just now, or an small and dense earthquake swarm that looks like an harmonic tremor spike.

    I am not sure yet what is the correct case now.

    1. Thank you for your tireless efforts and updates on these volcanoes, Jón. I’m very interested to see what happens with these particular volcanoes as my husband lives in the Netherlands and I’m in the United States. Don’t ask..long story…legal immigration appears to be rather complicated o.O.

      Anyway, if Katla does go off, I worry that I won’t be able to fly to see him at the end of this year because of ash, so I’m watching this very closely.

      Good luck with the switch to Gentoo!

      Khim~

  4. I am moving my desktop computer to Kubuntu Linux tonight from Gentoo Linux. If all goes well this is just going to take about 2 hours until I am fully back online.

    If there are problems this is going to take longer time. But then I just move to my laptop as an backup while I fix the problems.

  5. Jon, just when you thought you could come back, rest, relax, slowly move in and unwind from all the stress of moving, you get slammed with events. Damned Murphy.

    You doing a tremendous job under all the strain, financial, moving, OS migration. Pace yourself and I won’t feel bad if there is a lull in posts.

  6. Great. I hope it stays this way. My girlfriend is heading over here soon with airplane. Haven’t seen her in month.

    I hope no volcano would stop me from seeing her :@

  7. This is the first since yesterday with depth, quality 44.89%
    2011-06-18 20:30:04,0 63,633 -19,439 19,0 1,1 44,89 5,3 km SSA af Básum

  8. Jon, love your blog. Someone has to keep an eye on these sleeping monsters. 🙂

    > I am moving my desktop computer to Kubuntu Linux tonight from Gentoo Linux.

    As a longtime Linux user myself, I’ve been underwhelmed by Kubuntu. I’m planning on moving my install to Centos as soon as I have time. Here’s hoping you have a better experience.

    1. Well, so far Kubuntu is not doing good thins for me. There are problems with video (kmplayer plays then outside the frame when output is on auto). But I hope to solve that issue somehow. Not sure what is the actual issue, as I am using nvidia binary drivers.

      Before I move back to Gentoo Linux (in the case Kubuntu does not work for me). I want to see if I can solve the problems that I am dealing with at current time.

    2. Kubuntu is not doing what I hoped for. So I am going to move back to Gentoo Linux from tomorrow.

      The complete setup is going to take about three to four days in all.

    1. This is one of those “tectonic pushes”, this one from the South I think. Most are from the North. I am not seeing things that are not there am I ? They seem to happen in pulses. If- http://en.vedur.is/earthquakes-and-volcanism/earthquakes/ – was played as a month long video, I think thats what one would see. I have not tried ( I don’t know how) I just suspect that is the case. The activity goes up and down in long waves I think.
      Perhaps if we could see it like the animated- http://www.strikestareu.com/sslt/sslt.html -that weather/storm people also on the Internet enjoy, patterns would reveal themselves. Earthquakes and Volcanoes need more tools and more people thinking, for the good of people.
      Just like the storm radars, tools save lives.
      Sorry Renato Rio, I ranted a little there.

  9. Has “Mýrdalsjökull – earthquakes during the last 48 hours” gone quite quiet very quick?………………………. Bang? I often wonder how Katla will go. Weather Katla will go. Like the old saying “Lull before the storm” Perhaps Mýrdalsjökull will go quiet before anything drastic.
    I realise I could very well be totally wrong, but I just had to ask. Nature has her ways after all. One of her best overall is quiet then…

    1. Rustynailer:
      Tectonic pushes… I concur with you. I notice them happening again and again. When they start in the MAR, soon the wave reaches Reykjanes and Krýsuvik. Sometimes they extend either East (Hvólsvöllur, Arnes), or North (Langjökull); or else they start in Kolbeinsy ridge and Grimsey reaching down to Askja and Bardarbunga.
      There are no registers about the signs Katla gives us when she goes. But I’ve got a feeling that they would be more in the way Lady E did. Lots of swarms, rising in numbers and intensity. We are just seeing the beginning of it. Probably it will take another two or three months for the magma to come to light. If Katla erupts we may consider ourselves privileged. And there’s still a chance that we could see Hekla erupting and then again Grimsvötn. That would be great. Five Icelandic volcanoes withins a three-year lapse. 🙂

  10. Hello,

    I’m new to this blog I read, however, for several weeks. First of all, congratulations to Jon and others for their excellent work and follow-up information.

    Then, excuse my bad English. I speak French every day, because I come from Switzerland, and although I understand quite well English, write and speak is something else!

    Finally, what about this earthquake swarm beneath the volcano Katla. Can we expect an eruption within weeks or months? The volcano Grimsvotn had he not done the same in November 2010?

    Well, the pleasure from you.

  11. Would someone speak nicely to the nice people of the camera guys at ruv and see if they would please fix the camera at Katla.
    Thankyou so much

  12. I am not entirely sure whether Katla would need such a great earthquake activity before erupting. I mean it seems that as Icelandic volcanoes erupt more often, they tend to show less earthquakes before an eruption. For example, Grimsvotn or Hekla erupting every 6-11 years, show almost no earthquakes before the eruption.

    Differently, Eyjafjallajokull breaking its 200 years silence, showed earthquake swarms for 2 months before the eruption. Would Katla break its 100 years silence with 3-4 weeks of earthquakes? Probably not. The Eldfell volcano in the Westman Islands broke centuries of silence without any earthquake activity before (if I am not wrong). So, we might watch Katla erupting without only a few days of earthquake activity.

    Does anyone knows how Krafla behaved before its eruptions in the 1980s?

  13. There were earthquakes prior to Eldfell, but there weren’t enough seismograph stations at the time to triangulate the locations! I believe at the time, they thought Eyjafjallajokull was going to erupt!

    Preceding seismicity depends entirely on the individual plumbing system of each volcano, and indeed where the magma rises (i.e. is it a fissure swarm eruption or in the central volcano?). Hekla is an unusual case because it remains almost totally aseismic until only tens of minutes before an eruption. It’s believed the magma reservoir is very deep and the only seismicity here is caused by the magma making it’s final ascent to the surface.

  14. Most EQ´s has now been reviewed and 13 out of 21 is located less than a km deep (most at 0,1km).
    The icesheet is around 300m thick?

    Most of the recorded earthquakes would by that logic be ice quakes. And isn´t this a melting period?

  15. Yes, the ice sheet is 300-500 meters deep. So, earthquakes located 0.1 Km are on the ice cap, but Jon would be able to distinguish between icequakes and earthquakes (and they would not cause harmonic tremor). So far, most of them have been very small earthquakes. Except for a few that have been larger than 2.0 and even 3.0 a couple of days ago.

    I really think this is Katla awakening. Aren’t most eruptions around summer or autumn time, due to less ice pressure on the volcano?

  16. That’s the big question but I doubt that the sensors are above the ice, have qe be on something solid like a rock, that’s my opinion

  17. This one was not an icequake:
    Sunday
    19.06.2011 14:18:51 63.691 -19.130 5.3 km 1.7 83.83 8.2 km NE of Goðabunga

  18. If an earthquake is 0.1 km below the surface. They are meaning the rock, not the Ice. Ice-quakes do happen. But they are harder to detect and do not have the same signature as normal earthquakes.

      1. Jon, I haven’t check the helicorders, but as of todat there is no wind at all here in Grimsnes area. Katla is only some 100km east. It is a wonderful summer day in South Iceland.

        The 1-2 hz tremor seems to be increasing now around Katla, and the earthquakes continue.

      2. It is just the wind and the ocean waves. Nothing else is going on. Besides the earthquakes that are taking place inside Katla caldera.

        But earthquakes in Katla form spikes in Icelandic Met Office tremor charts.

  19. I am seeing earthquake swarm on Láguhvolar SIL station and on Rjúpnafell SIL station. But not on other SIL stations.

    That means the earthquakes are unlikely to appear on the automatic earthquake list on Icelandic Met Office web page.

    1. I have found laguhvolar SIL on the map but can’t find rjupnafell – where abouts is it?

  20. Low frequency tremor in Haukadalur has also increased steeply in recent hours. Could this mean something moving at Hekla?

    1. Hekla wont give much signs of unrest before erupting. An hour or two maybe?

    2. The tremor level is still not or not much above the normal level from the last days or weeks, so as long as it is not at least twice the normal maximum, it’s nothing unusual.

  21. And just to clarify my previous post regarding icequakes. I meant only that the swarm (magmatic part of it) isnt as big as it may seem. 🙂

    I definitely think that we will see Katla roar to life relatively soon scaring the crap out of all airline stockholders. Within a year. Note that it is only a guess and an amateurs view of it. 🙂

    On a positive note..Reporters worldwide will hve an easier time pronouncing it. 🙂

    1. Not just airline stocks, anything tied to flight transportation of perishables or items with low inventories, leisure-tourism-convention, or just any ETF/ETN fund tied long or short to the MSCI Europe index (EPV). The only thing that would most assuredly go up would be large shipping/trucking stocks, water treatment, masks sales and the dollar index funds againts the euro. People don’t realize the potential catastrophic effects of a large, extended eruption on global economies, especially given the fragility of the euro zone currently.

      Interesting article on the potential effects of a Katla eruptoin on the UK
      ftp://ftpext.usgs.gov/pub/er/va/reston/International%20Ash-Aviation/Related%20Documents/Lacasse%20et%20al_Katla%20ash%20hazards_Chapman%20Conference_June%202002.pdf

    2. “On a positive note..Reporters worldwide will hve an easier time pronouncing it.”

      Good luck with that around here. These morons are good to pronounce their own names.

    3. Perhaps Presthnjúkar volcano will erupt, would like to hear news readers pronounce that! 🙂

  22. I was wondering, if there is some way of monitoring gases coming from volcanoes such as Hekla, some hiker who was jogging at the roots of Hekla at Selsund dropped dead for no apparent reason yesterday, it crossed my mind that there might be a connection to Hekla, probably just being silly though 🙂

      1. “Volcanoes release more than 130 million tonnes of CO2 into the atmosphere every year. This colorless, odorless gas usually does not pose a direct hazard to life because it typically becomes diluted to low concentrations very quickly whether it is released continuously from the ground or during episodic eruptions. But in certain circumstances, CO2 may become concentrated at levels lethal to people and animals. Carbon dioxide gas is heavier than air and the gas can flow into in low-lying areas; breathing air with more than 30% CO2 can quickly induce unconsciousness and cause death. In volcanic or other areas where CO2 emissions occur, it is important to avoid small depressions and low areas that might be CO2 traps. The boundary between air and lethal gas can be extremely sharp; even a single step upslope may be adequate to escape death.”

        From USGS http://www.usgs.gov/

    1. It was a “hot” day yesterday per Icelandic standards. The maximum hit 23ºC where I live. Running 30km in such a sunny warm day at the base of Hekla, which is a desert of sand and ash (and still blowing ash from the Grimsvotn eruption), is not a very pleasant experience at all!

      It is just if you go to a depression like a crater that you can die of gas intoxication. If you are in the open, you only feel the gases, but they will generally not harm you. But this is my beginner experience with living close to volcanoes.

    1. Very nice collection. Thank you.

      Enough to keep reading for a few hours. 🙂

    2. Looking at that data, maybe a third volcano between Eja and Katla?

      Thanks Jon and everyone for all the hard work and info with the ongoing events.

      1. Rick. Regarding the “third volcano”. That would be Fimmvörduhals which started erupting last year as a precursor to Eyjafjallajökulls eruption. It was a smaller fissure event.

      2. Yeah I remember that. Sputtered away quite nicely it did. Even looked like a blow torch at times. Then another rift opened nearby, both faded in activity. Swarm kicked in and shot over to beneath the central vent and European air traffic had a mess.

  23. In all three online news that I’ve read is that a 50 year old man died suddenly and without suffering on a hike. These are all the information!
    If the death had been caused by gases, the authorities had responded immediately!

  24. http://en.vedur.is/media/vedurstofan/utgafa/skyrslur/2009/VI_2009_013.pdf
    I have just been reading this and I see some similarities between This information from Eyjafjallajokull and what we seem to be seeing at the moment under Myarsdaljokull.
    Maybe not an eruption but surely magma moving to form a sill or dyke. If it was purely tectonic then we wouldn’t be seeing these harmonic waves and here I am talking deep to mid range activity.
    I am an amateur at all this. but again more small quakes today in a very tight cluster. This is very interesting as we will be able to watch the story unfold. Not a Katla Monger here but for the first time I can listen to so many ideas and theories and real time information on a volcanic area. Thank you Jon and all who participate

  25. @ RonF…….. Yup! This will keep me quiet tonight. Husband will be able to have full control of the TV remote control! He sends many, many thanks for this amount of reading material 🙂

  26. Domestic news | disaster | 19/06/2011 15:52

    More than a thousand earthquakes in May
    More than one thousand earthquakes were detected in this country in May, months, most of the Vatnajökull as might be expected, which erupted in Grímsvötn in the second half of the month.Under Vatnajökull detected 185 earthquakes in May.According to a statement on its website service.About 180 earthquakes were detected in Tjörnes fracture zone, the Northeast, the largest was a 3.4 on the Richter scale, west of Grimsey.Under Mýrdalsjökull scored 131 earthquake in May, but 51 were within the Katla caldera and the most powerful was about 1.5 on the Richter scale.Today, the cycle of small tremors have been on the eastern Reykjanes Kaga and the South, but there is no evidence that further developments are looming. They are starting to watch….

  27. New geothermal area found on the bottom of Kleifarvatn lake:
    http://www.ruv.is/frett/islandsmet-i-djupkofun

    Á fimmtudaginn fundu kafararnir áður óþekkt hverasvæði á botni Kleifarvatns. Sigurður segir að þeir hafi orðið agndofa. Allt í einu hafi þeir sé brún á 60 metrum sem hafi verið þverhnýpt niður. Þar hafi opnast fyrir risa svæði
    On Thursday, divers found a previously unknown geothermal area at the bottom of Lake Kleifarvatn.

      1. Indeed. Alot of seismisity and a new geothermal feature? An eruption shouldnt be too many years off.

    1. Can anyone translate the text any better than Giggle does? What exactly have they found?

      1. They found an new hydrothermal area on the bottom of Kleifarvatn lake. Along with an deep and sharp new fracture in the lake it self. The fall of depth is around 40 meters according to this news.

        The Krýsuvík volcano area appears to be getting more active in terms of hydrothermal activity.

      2. Ahh, so that’s what they found. Makes alot more sense than the dreaded google translation from Icelandic to English! 🙂

  28. Hello,
    living in Napoli at the moment and getting a bit nervous about Vesuvius. Was watching
    http://www.ov.ingv.it/index_eng.htm click the Real time seismic signals link and chek out the seismic chart of Vesuvius BKE V…I don´t understand it, but it looks very active to me… I will continue my work here for one month and I beg that Vesuvius won´t go off anytime soon. I know this is site dedicated to Icelandic volcanoes but since there are a lot of ppl here with know-how on seismic readings I really beg you to say what those means…is the volvano awakening??!

    great site by the way, read it daily!
    Johan

  29. My next post is going to be when I have my main computer back up. I hope that too be soon. But Gentoo Linux is do it your self linux distro, so things take time.

    My first attemt at re-installing Gentoo Linux with 32bit minimal install did fail due to some odd system error. Now I am trying the 64bit version and I hope it works. But so far it has done so I think.

  30. Sorry I’m not an expert, but it looks like the tremors are increasing at Katla. Just what I think.

    1. Yes it seems a small (for the moment) harmonic spike in the tremor charts.

      1. No i meant the beginning of the tremor spike. Seems a bit dense. Especially GOD SIL station. And I am not sure what is up with Alftagrof which is between Myrdalsjökull and the coastline. Probably some bad weather or wind but strange that only the high frequency band is affected. And there was a few quakes at that spot a while back.

      1. Yes Boris is definitely the guy to ask. And if im not mistaken the issue of vesuvius was raised a few days ago by someone on the blog. I recall him referring to alot of mining and other man made noises.

        But ask him and you will recieve a good and easily understandable answer. 🙂

  31. @ Jón or any other with more knowledge about the Icelandic landscape.

    Will there be any difference in the waterflow at Hólmsá or Eldvátn if Katla starts melting the glacier? Of course it may depend of the location of the eruption but are they typical places for a Jökulhlaup?

    The current increase in water flow at Eldvátn is due to seasonal melting right?

  32. @Johann
    I had a similar reaction when I visited here for the first time. I really thought vesuvius was about to go Pompeii!
    http://digilander.libero.it/meteo_ercolano/
    If however you look at the pattern of these recordings the huge “Earthquakes” are at regular intervals and occur only during the day time. This suggests that it is possibly a regular train service or some such thing.
    I found these videos really helpful in learning how to recognise an earthquake and to be able to filter out vibrations caused bu wind, sea, traffic, planes and trains etc.
    http://digilander.libero.it/meteo_ercolano/

    http://qvsdata.wordpress.com/learning-links/understanding-seismograms-and-earthquakes/understanding-seismos-liss-helis/

    I hope I have put your mind at rest and you can unpack your bags and enjoy the beauties of the Bay of Naples.

    http://qvsdata.wordpress.com/learning-links/understanding-seismograms-and-earthquakes/understanding-seismos-liss-helis/

  33. Question for the locals here. I found this website earlier with (what I assume to be) a lot of traffic cameras. Not that there is any traffic on any of them!

    Anyway, do any of them have Hekla or Katla (or any other points of interest) in the background?

    Thanks in advance!

  34. Magnitude mb 4.3
    Region REYKJANES RIDGE
    Date time 2011-06-20 21:20:20.5 UTC
    Location 53.31 N ; 35.73 W
    Depth 200 km
    Distances 1355 km NE Saint john’s (pop 112,007 ; local time 18:50:20.5 2011-06-20)
    1379 km NE Conception bay south (pop 17,087 ; local time 18:50:20.5 2011-06-20)
    956 km SE Nanortalik (pop 1,509 ; local time 19:20:20.5 2011-06-20)

    Magnitude mb 4.6
    Region REYKJANES RIDGE
    Date time 2011-06-20 21:16:53.7 UTC
    Location 53.54 N ; 35.44 W
    Depth 33 km
    Distances 1382 km NE Saint john’s (pop 112,007 ; local time 18:46:53.7 2011-06-20)
    1398 km SW Hafnarfjörður (pop 22,289 ; local time 21:16:53.7 2011-06-20)
    945 km SE Nanortalik (pop 1,509 ; local time 19:16:53.7 2011-06-20)

  35. Is Reykjanes Ridge a huge area? I thought it was just that spur off South Western Iceland that is shown on the IMO website.

    1. This is about 10 degrees to the south and 10 degrees to the west. (around 53° north and 35° west). Reykjavik is around 64 north and 23 west.

      1. Ever wear a hat? Hat rhymes with lat and latitude runs up and down. How long are your arms? Longitude runs east and west, from side to side… like your arms.

  36. Off-topic: Darn. I had written an long explanation. But I did just close the window by accident. Please replay to this by pressing the replay on this message. Not somewhere else. This is also off-topic the discussions here.

    I was helping my friend setting up an new motherboard and computer tonight. When he did plug his external hard drive into the front USB connector the Windows did notice and usb failure and part of the usb connect side on the external hard drive did get really warm. After that his external hard drive has stopped working. I think that the hard drive it self is still working. But the usb interface has burnt out due to too high voltage from the usb connector. While connected it got really warm and then it stopped working.

    I am not sure how that did happen. But this was the front usb connector that you connect with wires on the motherboard. I am not sure why they did give too much power into the external hard drive. Because that should not have happened at all.

    His external drive is at Iomege type. Most likely eGo Helium. But it is black. The usb cable splits at the end, one for power and one for data. The green light turns on when I plug it in. But nothing else happens. The drive does not power up and is not checked into the Windows as it should do.

    What I need to know is how to open up the box in order to get the hard drive out. I think that his data is still save and good. I want to get the hard disk out of this box, but I do not find any good way to open it. I want to buy him an new box (it only costs 2450 ISK, 14,81€, 21,09$, 110,44 DKK) to use with his hard drive.

    Since I do think that I might have done an mistake by connecting the usb connectors to the motherboard in the first place. There is an good chance that I did somehow connect them wrong. But I am just not sure how at this moment. I might have connected the wires wrongly on the motherboard with this results.

    The question is. How do I open this hard drive box ? I have looked for screws. But not found them. But I suspect that they are holding the box together.

    The model is marked by hsdup2 (I think).

    Thanks for the help, sorry for the off topic.

    1. If you can not see screws, it held closed by clips. It seems, it was a low-quality build as it was designed to be not-repairable. So you do not lose much the “tear” it open. I said tear, as typically you have to break the clips to open it.

    2. Dear Jón,

      It seems impossible that too high voltage (power) has caused the extern harddisk to stop, because all the voltage in the computer is 12 Volts (like in a car). The power suply (PSU) transforms the 220 in 12 Volts; if the PSU is malfunctioning of course you could experience problems, but then there would be more components not working properly (or burnt because of too high of a voltage). Your idea is good I think: you see a green light on the cover of the disk, so there is power; somehow this power is not reaching the harddisk itself.
      It also could be that a (thermal) fuse inside the case of the HDD is burnt by a high voltage peak.
      Don’t be sorry for the off-topic: it’s your blog! you’re entitled to make an exception!

      Kind regards and good luck!

      Henk (Zwaag, Holland)

    3. I am not sure why it got the wrong amps (rather then voltage) into it. That should not have happened at all.

      Maybe the fault was already there. The older motherboard that I did replace already had faulted caps and was not working properly. But whatever the case now. I am going to buy my friend an new external hard drive box, so he can continue to use his 300GB hard drive. He told me that he has important data on that drive.

  37. Just checked weather. Strongest wind speed is 5 off shore south of Godabunga. Inland force 2. I am not convinced wave power on the coast would create this much tremor.

  38. There is an tremor spike taking place in Katla volcano. It is strongest on Lágu Hvolar SIL station. It is getting higher then the background noise (wind, ocean waves, traffic, etc..). The tremor is currently strongest on four SIL stations.

    hvo. – Strongest.
    rju. – Rather weak.
    sly. – Strongest spikes appear there.
    god. – Medium strength on it there.

    Spikes can also be seen on other SIL stations around Katla volcano.

    It is impossible to know if this is going result in an earthquake swarm, as it did happen last time.

    I am going to write about this in few hours. I need an small break after todays work.

Comments are closed.